Problem: $-\dfrac{8}{5} + \dfrac{9}{6} = {?}$
Explanation: $ = - {\dfrac{8 \times 6}{5 \times 6}} + {\dfrac{9 \times 5}{6 \times 5}} $ $ = - {\dfrac{48}{30}} + {\dfrac{45}{30}} $ $ = - \dfrac{{48} + {45}}{30} $ $ = -\dfrac{3}{30}$